Systemic tPA Treatment for Thrombosis in a Patient with Dilated Cardiomyopathy on Berlin Heart

Introduction ite advances in anticoagulation management in pediatric VAD, thrombosis and stroke remain a major concern. For patients with thrombosis who fail intensification of standard anticoagulation options are limited. We present a case of thrombosis in a patient on Berlin Heart LVAD that was successfully treated with systemic alteplase. Case Report The patient is a 2 year old 13.6 kg girl (BSA 0.58) with dilated cardiomyopathy and left ventricular systolic heart failure necessitating placement of a Berlin Heart EXCOR LVAD as a bridge to heart transplantation. She was implanted with a 15mL pump at a rate of 100 beats/min. There were no intra-operative complications and anticoagulation was initiated with bivalirudin; target PTT 70-90 sec (achieved consistently by POD#3). On POD#5 she became febrile with rising inflammatory markers and broad spectrum antibiotic therapy was initiated. She then required escalating doses of bivalirudin for decreasing PTT values. After negative blood cultures for 24 hours, she completed a course of pulse steroids for possible inflammatory reaction on the pump. She was also started on aspirin and then dipyridamole. By POD#15, she had an escalating respiratory support requirement in the setting of a large pleural effusion and bivalirudin was held briefly for placement of a chest tube. Despite no obvious fibrin or clot in the device or cannulas, an echocardiogram a revealed a 5mm thrombus in the left ventricle adjacent to the inflow cannula. Given the position of the thrombus, clot extraction by surgical or cardiac catheterization was deemed not feasible due to limited ability to perform thrombectomy without embolization. Therefore, we treated medically with systemic alteplase while maintaining the patient on continuous bivalirudin infusion at lower PTTs. We achieved successful resolution of the thrombus by echocardiogram with no significant complications or neurologic deficits. The patient was supported by the Berlin Heart for 5 months until transplant with no other complications. On evaluation of the explanted heart there was no residual thrombus. A head CT performed after heart transplant for follow up of an unrelated concern revealed no evidence of intracranial hemorrhage or infarct. Summary Systemic tPA may be considered as a treatment option in patients with thrombosis on ventricular assist device in lieu of more invasive treatment options.